1. Field of the Invention
This invention relates to knitted mesh fabric and a process for knitting that fabric. The fabric is applicable for manufacturing a fleece retaining coat for fitting to a fleece bearing animal during biological shearing. It will be convenient to hereinafter disclose the invention in relation to that exemplary application, although it is to be appreciated that the invention is not limited thereto and may have a wide range of other applications such as wrapping or covering material and as a shade or protective canopy of a covering structure.
2. Description of the Prior Art
It is known to biologically xe2x80x9cshearxe2x80x9d sheep using a biological depilatory xe2x80x9cdefleecingxe2x80x9d agent, such as epidermal growth factor. The defleecing agent causes a weakening or break in the wool staple at or near the skin surface, enabling the fleece to be easily removed.
Various coats have been proposed to be fitted to the sheep following administration of the defleecing agent so as to prevent uncontrolled removal and loss of the fleece. Australian patents 647084 and 655870, and applications 60853/73, 40926/96 and 65570/99 all disclose mesh or net fabric coats which are fitted to at least the body of the sheep so as to retain the fleece about the body as it separates from the skin. The mesh openings in the fabric are sized so as to retain the fleece but allow it to breath as well as enable moisture to escape from the coat.
A feature of these prior coats is that the mesh fabric has no more than a quite limited ability to stretch. That stretching is usually confined to the amount of localised xe2x80x9cgivexe2x80x9d within stitches or connections between threads of the fabric. The dimensional stability of the fabric has been considered essential to prevent the fleece from moving on the sheep as it separates from the skin. The fleece is quite heavy, particularly when wet, and there have been concerns that the coat will stretch out of shape under weight of the separating fleece and the fleece will then collect under the neck and around the logs and belly of the sheep.
However, a problem with coats composed of fabric with limited stretch is that they will neatly fit only a very limited range of sheep. In particular, coats of a specific size tend to only properly fit one size sheep of a designated breed having a specified wool staple length. If the coat is over size then it will not support or retain the separating fleece in position on the sheep. Alternatively, if the coat is under size then it can be difficult to fit and will cause discomfort to the sheep, and can also make it difficult to separate the coat from the fleece when removed from the sheep.
This problem can be addressed by providing different sized coats to fit the various sizes of sheep within a flock. However, that increases the coat inventory required to be maintained by sheep shearers and owners. It will also complicate the procedures for coat fitting, adding to fitting time. These difficulties, in turn, can increase the cost of biologically shearing sheep.
It is an object of the present invention to provide a relatively simple knitted mesh fabric which has substantial resilient stretch qualities in at least one direction.
It is a further object to provide a knitted mesh fabric which has a degree of resilient stretch which makes it particularly suitable for use in the manufacture of fleece retaining coats for fitting to various sizes of fleece bearing animals.
It is another object to provide a knitted mesh fabric which has sufficient resilient stretch for use in the manufacture of fleece retaining coats for fitting to different breeds of fleece bearing animals.
With these objects in mind, the present invention in one aspect provides a knitted mesh fabric including:
an open framework of longitudinally and transversely extending knitted threads; and,
a plurality of resiliently, longitudinally extendible threads laid in the open framework in at least one direction, the open framework being contracted in the at least one direction when the resiliently extendible threads are in a relaxed or non-extended condition, whereby the open framework can be extended in the at least one direction causing the resiliently extendible threads to resiliently extend and the fabric to resiliently stretch.
In another aspect of the present invention, there is provided a process for warp knitting a resiliently stretchable mesh fabric, including:
(a) feeding a plurality of warp threads to a warp knitting machine in accordance with a predetermined knit pattern;
(b) knitting the warp threads together in a predetermined knit pattern to form an open framework of longitudinally and transversely extending knitted threads;
(c) feeding a plurality of resiliently, longitudinally extendable threads to the warp knitting machine; and
(d) laying the resiliently extendible threads in the open framework in at least one direction thereof during knitting of the open framework so that the open framework is contracted in the at least one direction when the extendible threads are in a relaxed or non-extended condition.
In a further aspect of the present invention, there is provided a product, such as a fleece retaining coat, manufactured from the above mesh fabric or using the above process.
It should be understood that the term xe2x80x9cthreadxe2x80x9d as used herein includes mono- and multi-filament threads, and also two or more threads which are twisted or drawn together for knitting with other threads.
Preferably, the knitted threads form an array of thread connections extending in spaced apart rows along the longitudinally extending threads. The resiliently extendible threads are preferably laid in the longitudinal direction of the framework. In this way, the framework is contractible and extendible in the longitudinal direction.
Preferably, the resiliently extendible threads extend along the rows of thread connections. In one preferred arrangement, the resiliently extendible threads extend one each along each row of thread connections.
Preferably, the longitudinally extending threads are knitted into pillar stitches.
Preferably, the resiliently extendible threads are laid in some only of the pillar stitches. In one preferred arrangement the resiliently extendible threads are laid in the pillar stitches in a regularly repeating sequence. In one form, the resiliently extendible threads weave between opposite sides of respective rows of thread connections, through the pillar stitches, and along the rows of thread connections.
In one preferred arrangement, the resiliently extendible threads are laid in without locking stitches.
In an alternative preferred arrangement, the resiliently extendible threads are laid in with locking stitches so as to lock the resiliently extendible threads into the framework. The locking stitches are preferably knitted with some of the pillar stitches. In one form, each resiliently extendible thread has at least one locking stitch in each repeat of the knit pattern of the open framework.
Preferably, each resiliently extendible thread has a core filament of rubber and an outer cover of yarn spiral wrapped about the core filament.
Preferably, the longitudinally extending threads are knitted in spaced apart rows, and the rows of threads adopt a zigzag configuration generally in the plane of the open framework when the framework is contracted.
In a further aspect of the present invention, there is provided a knitted mesh fabric, comprising an open, generally planar framework of knitted inelastic threads including rows of spaced apart, knitted threads; and a plurality of elastic threads laid along the rows of threads, and weaving between opposite sides of respective inelastic thread rows. The open framework is contracted when the elastic threads are in a unstretched condition. The threads of the framework remain generally in the plane of the contracted framework and the rows of threads fold in a zigzag configuration into spaces between the rows so as to partially close the spaces, whereby extending the contracted framework in a direction of the rows causes the elastic threads to resiliently stretch and the rows of inelastic threads to unfold so as to open the spaces.